Written round then 3 f2f rounds over multiple days; HR ghosted after promising feedback

Application

I interviewed at Zomato

Interview

First was a written round, two question on a sheet of paper, I needed to write the solution. We had to wait for about 2 hour to get the answer sheet evaluated. After that 1 f2f round, after which I was told to come after 2 days for next set of rounds. After 2 days I had 2 more f2f rounds. The duration of the wait between rounds was on average 1 hour. The HR told me he will give feedback after consulting the panel. There was no feedback in subsequent days, even tried reaching him but he always hung up on me.

Interview questions [1]

Question 1

f2f round 1 1) reverse a linked list 2) detect a loop in linked list 3) Puzzle f2f round 2 1) sort an array with 1's and 0's 2) swap two numbers without extra variable 3) Find number of 1's in a row wise sorted matrix with 1's and 0's f2f round 3 Design a system which gets some event at regular interval and we should be able to fetch events within given input timerange.